Question

how many moles of solute partielces are present in 1 mL following aqueous solutions?

a) 0.02 mol CuSO4 in 1 liter of solution

b) 0.08 mol pyridine (C5H5N) in 1 liter of solution

c) 0.004 mol Ba(OH)2 in 1 liter of solution

d) 10 grams of NaCl used to make 100 mL of solution

Answer 1

a) 0.02 mol CuSO4 in 1 liter of solution

THUS 0.02 /1000 = 0.00002   mol in 1ml

b) 0.08 mol pyridine (C5H5N) in 1 liter of solution

THUS 0.08 /1000 = 0.00008 mol in 1ml

c) 0.004 mol Ba(OH)2 in 1 liter of solution

THUS 0.004 /1000 = 0.000004 mol in 1ml

d) 10 grams of NaCl used to make 100 mL of solution

molarity = wt / mwt x 1000/volume

             = 10/ 58.5 x 1000/ 100

              = 1.71 M

OR 1.71 mol NaCl in 1 liter of solution

THUS 1.71 /1000 = 0.00171 mol in 1ml